Dorsey Dfvpd — 93V151000
Summary
IMPROPER ROUTING OF THE AIR BRAKE HOSES FROM THE BRAKE VALVES TO THE BRAKE CHAMBERS OF THE AIR OPERATED S-CAM BRAKES CAN CAUSE THE HOSES TO CHAFE OR BE CUT ON THE TRAILER FRAME.
Consequence
SERVICE BRAKE HOSE CHAFING OR CUTTING CAN CAUSE REDUCTIONOR LOSS OF SERVICE BRAKES WITHOUT PRIOR WARNING TO THE DRIVER. A VEHICLE CRASHCAN OCCUR AS A RESULT OF THE MALFUNCTIONING SERVICE BRAKES. ALSO, IF A SPRINGBRAKE HOSE IS CUT, THE SPRING BRAKE DRAG OCCURS, WHICH REDUCES THE EFFECTIVENESSOF THE SERVICE BRAKES, AND CAUSES BRAKE COMPONENTS TO OVERHEAT TO THE POINT OFIGNITING THE UNDERCOATING AND BURNING THE TRAILER. THIS CAN ALSO CAUSE WHEELLOCKUP WHICH COULD RESULT IN A VEHICLE CRASH.
Remedy
CHAFFED BRAKE HOSES WILL BE REPLACED, AND THE BRAKE HOSE ROUTING AND BRAKE CHAMBER INSTALLATION WILL BE MODIFIED TO ELIMINATE THE BRAKE HOSE CHAFFING PROBLEM.